Câu 2. Tính:
a) 0,75 - $\frac{5}{6}$ + 1$\frac{1}{2}$ = $\frac{3}{4}$ - $\frac{5}{6}$ + $\frac{3}{2}$ =$\frac{9}{12}$ - $\frac{10}{12}$ + $\frac{18}{12}$ = $\frac{17}{12}$
b) $\frac{3}{7}$ + $(\frac{4}{15})$ + $(\frac{-8}{21})$ + (-0,4) = $\frac{3}{7}$ + $(\frac{4}{15})$ + $(\frac{-8}{21})$ + $(\frac{-2}{5})$ = $\frac{45}{105}$ + $(\frac{28}{105})$ + $(\frac{-40}{105})$ + $(\frac{-42}{105})$ = $(\frac{-9}{105})$ = $(\frac{-3}{35})$
c) 0,625 + $(\frac{-2}{7})$+ $(\frac{3}{8})$+ $(\frac{-5}{7})$ + $1\frac{2}{3}$
d) (-3). $(\frac{-38}{21})$ $(\frac{-7}{6})$.$(-\frac{3}{19})$
e) $\frac{11}{18}$ : $\frac{22}{9}$. $\frac{8}{5})$ = $\frac{11}{18}$ . $\frac{9}{22}$. $\frac{8}{5})$ = $\frac{1}{4}$ . $\frac{8}{5})$ = $\frac{2}{5}$
g) $[(-\frac{4}{5})$ . $\frac{5}{8})]$ : $(-\frac{25}{12})$ = $[(-\frac{4}{5})$ . $\frac{5}{8})]$ . $(-\frac{12}{25})$ = $[(-\frac{1}{2})$ . $(-\frac{12}{25})$ = $(\frac{6}{25})$